Axons descend from the centrum semiovale to the posterior limb of the internal capsule

From the internal capsule, fibres continue to the middle portion of the cerebral crura

Fibres continue to the basal part of the pons, where they form connections with pontine nuclei

Exiting the pons, two columns form on the external surface of the medulla oblongata

80% fibres decussate (cross-over) at the junction between the spinal cord and medulla oblongata and continue to descend on the lateral aspect of the spinal white matter as the lateral cortico-spinal tract

Those that don't decussate, continue in the anterior spinal white matter as the anterior cortico-spinal tract